摘要:
The present disclosure relates to a method to determine the phase of a signal when transmitter and receiver circuits use separate clocks. A discrepancy between the separate clocks is determined, as is a correction factor between the separate clocks. The phase is determined using a measured time of arrival of the signal, the determined discrepancy, and the determined correction factor. A drift factor and an expected start time of a pulse sequence may be used to determine the discrepancy. A start time of a pulse within the pulse sequence is determined and used to determine the correction factor. The method works by either absolute synchronization of the separate clocks, or by making the measurements independent of clock synchronization.
摘要:
A resistivity array having a modular design includes a transmitter module with at least one antenna, wherein the transmitter module has connectors on both ends adapted to connect with other downhole tools; and a receiver module with at least one antenna, wherein the transmitter module has connectors on both ends adapted to connect with other downhole tools; and wherein the transmitter module and the receiver module are spaced apart on a drill string and separated by at least one downhole tool. Each transmitter and receiver module may comprise at least one antenna coil with a magnetic moment orientation not limited to the tool longitudinal direction. A spacing between the transmitter and receiver module may be selected based on expected reservoir thickness.
摘要:
The present disclosure relates to a method to determine a characteristic of a subsurface formation using electromagnetic coupling components. A downhole logging tool having one or more transmitters and one or more receivers, and being capable of measuring the electromagnetic coupling components is provided. The electromagnetic coupling components are measured using the downhole logging tool and used to form a 3-D Lateral Indicator and/or a 3-D Longitudinal Indicator. The 3-D Lateral Indicator and/or the 3-D Longitudinal Indicator are used to determine the characteristic of the subsurface formation.
摘要:
The present disclosure relates to a method to determine the phase of a signal when transmitter and receiver circuits use separate clocks. A discrepancy between the separate clocks is determined, as is a correction factor between the separate clocks. The phase is determined using a measured time of arrival of the signal, the determined discrepancy, and the determined correction factor. A drift factor and an expected start time of a pulse sequence may be used to determine the discrepancy. A start time of a pulse within the pulse sequence is determined and used to determine the correction factor. The method works by either absolute synchronization of the separate clocks, or by making the measurements independent of clock synchronization.
摘要:
An apparatus for making a resistivity measurement of an underground formation surrounding a borehole is provided. The apparatus includes a conductive tool body, at least one current injector electrode positioned between the tool body and a wall of the bore hole, at least one current return electrode positioned between the tool body and the wall of the bore hole, an electrical measurement device configured to monitor a voltage or a current signal indicative of an impedance imbalance, a regulator connected to the electrical measurement device, whereby the regulator is configured to receive the voltage or the current signal indicative of the impedance imbalance and is configured to generate an adjustment signal based on the voltage or the current signal indicative of the impedance imbalance.
摘要:
The invention discloses a method for electromagnetically measuring physical parameters of a pipe that includes measuring a pipe inner diameter ID and a pipe ratio of magnetic permeability to electrical conductivity μ2/σ2 by means of a measuring arrangement 1 comprising a transmitter coil 2 and a receiver coil 3, both coils being coaxial to and longitudinally spaced from each other, the measuring arrangement being adapted to be positioned into the pipe CS and displaced through the pipe.
摘要:
A resistivity tool is used with wired drill pipe and one or more wells. The resistivity tool has a transmitter, receiver modules located adjacent to the drill bit, and high sensitivity receiver modules located at greater distances from the drill bit relative to the receiver modules. The receiver modules and/or the high sensitivity receiver modules may also perform repeater functions for the wired drill pipe. The resistivity tool may provide information regarding a subsurface region of interest. The resistivity tool may be used in a system with sensors, and a distance between the sensors may be based on the type of measurement obtained by the sensors.
摘要:
A resistivity array having a modular design includes a transmitter module with at least one antenna, wherein the transmitter module has connectors on both ends adapted to connect with other downhole tools; and a receiver module with at least one antenna, wherein the transmitter module has connectors on both ends adapted to connect with other downhole tools; and wherein the transmitter module and the receiver module are spaced apart on a drill string and separated by at least one downhole tool. Each transmitter and receiver module may comprise at least one antenna coil with a magnetic moment orientation not limited to the tool longitudinal direction. A spacing between the transmitter and receiver module may be selected based on expected reservoir thickness.
摘要:
An electromagnetic imaging apparatus and method for electromagnetically measuring physical parameters of a pipe CJ, CC by means of a plurality of measuring arrangement ZMA, MCMA, MonMa, ImMA comprising a plurality of transmitter coil ZTX, LFTX, DTX and a plurality of receiver coil ZRX1, ZR2, MRX, MC, PRX1, PRX2, PRX3, PRX4, PRX5, PRX6, PRX7, PRX8, PRX9, PRX10, PRX11, PRX12, PRX13, PRX14, PRX15, PRX16, PRX17, PRX18, the transmitter coils and receiver coils being associated so as to form the plurality of measuring arrangement, the plurality of measuring arrangement being adapted to be positioned into the pipe and displaced through the pipe, the physical parameters being measured for a plurality of position along the pipe.
摘要:
A resistivity array having a modular design includes a transmitter module with at least one antenna, wherein the transmitter module has connectors on both ends adapted to connect with other downhole tools; and a receiver module with at least one antenna, wherein the transmitter module has connectors on both ends adapted to connect with other downhole tools; and wherein the transmitter module and the receiver module are spaced apart on a drill string and separated by at least one downhole tool. Each transmitter and receiver module may comprise at least one antenna coil with a magnetic moment orientation not limited to the tool longitudinal direction. A spacing between the transmitter and receiver module may be selected based on expected reservoir thickness.